Schizophrenia and schizoaffective disorder are associated with disproportionately high societal costs related to treatment, disability, and morbidity/mortality. Patients' nonadherence to medications and psychosocial treatments undermine the long-term management of these illnesses, making it difficult to achieve improved quality of life and ultimate recovery. Patients are at particularly high risk of treatment gaps and poor coping during the transitional period from inpatient hospitalization to outpatient care. Our long-term goal is to improve the continuity of care for patients with psychosis by supporting a safer and more efficient transition from inpatient to outpatient services. Our objective, which is the next step in attaining this long-term goal and building on our previously funded work, is to examine the feasibility, acceptability, and preliminary efficacy of a mobile device-delivered app, called Mobile After-Care Support (MACS), to improve patients' self-coping and medication and appointment adherence following a hospitalization. We hypothesize that MACS, a response- adaptive mobile app using empirically-supported cognitive behavioral strategies for psychosis, will lead to increases in the target mechanisms of self-coping and medication/appointment adherence, which will produce improvements in symptoms, and secondarily functioning and rehospitalization rates. Thus, establishing MACS as a viable adjunctive treatment aid during the critical months immediately post-discharge will provide essential data on a pathway to improved outcomes in adults with psychosis. The aims of this proposal are: (1) to use an iterative process to refine a new mobile aftercare app by conducting an initial open trial (n=10); and (2) to conduct a pilot randomized controlled trial (n = 50) of MACS vs. a mobile app time and attention control condition to examine its preliminary effects. During the open trial, we also will collect qualitative data from local stakeholders (e.g., patients, clinicians, administrators) to improve the intervention in preparation for the randomized phase of the project and to establish clinicians' preferences for receiving clinical data from MACS. The sample will consist of 60 patients total with schizophrenia-spectrum disorders, recruited during an inpatient psychiatric hospitalization and transitioning to outpatient care at local community mental health centers. Patients will use MACS up to 4 months post-discharge, during which time we will longitudinally assess their usage and outcomes. The approach is innovative in that it departs from the status quo by targeting this high risk and understudied phase in the continuum of care and by delivering a brief intervention in real-time via an app on patients' mobile phones. Successful completion of the proposed project will contribute significant actionable data on the feasibility and acceptability of MACS and its initial effects on coping, treatment adherence, and subsequent clinical outcomes (symptoms, functioning, rehospitalization). Data from this project will inform the future large-scale testing of MACS as a simple and potentially disseminable tool to aid patients' re-entry into the community after being hospitalized for psychosis.